- 9th June 2021
- Posted by: Dom Senior
- Category: Blog
We invited Professor John Dora to share his thoughts on the use of Flood Foresight technology to create an effective risk forecasting service for railway operators.
A Fellow of the Institution of Civil Engineers and member of the Thames Regional Flood and Coastal Committee, Professor John Dora offers advice to Governments, Academia, Regulators, Infrastructure Operators and Service Providers on resilience to weather and climate change. A highly respected expert in his field, we were delighted to work alongside John on a recent project and in the guest blog below he details how Flood Foresight can be used by rail and other infrastructure operators in the management of surface water risk.
Railway weather risk on the GB mainline network is managed using passive systems, with data presented as hazards. Knowledge of the vulnerability or exposure of rail infrastructure can be used if experienced managers/engineers are briefed and available, and asset risk registers may also be consulted.
Current forecasts are not sufficiently accurate enough and so early in 2020 we came up with a First of a Kind (FoaK) proposal, which combines technological advances that have emerged over the past 15 years. In previous work, we provided Network Rail with detailed mapping of vulnerable locations (earthworks – cuttings, embankments) from their potential exposure to surface water hazards. Linking this data with rainfall weather forecasts that show the surface water accumulations (i.e. the hazards) some days ahead, has the potential to produce accurate risk information that can be used to create a risk forecasting service for railway operators.
However, the concept of sourcing sufficiently accurate weather forecasts (from any forecasting system) needed to be proved. This is the thrust of the DfT and Innovate UK funded, FoaK 2020 project, to use Flood Foresight methodology to accurately forecast the likelihood of extreme surface water events. We believe that as no weather/infrastructure risk models with this level of forward-looking detail are known to be available, such a ‘proof of concept’ would help to show that this kind of state-of-the-art technique can improve the safety and operations of railways. Likewise, the technology may also be applied to other infrastructure systems that might be impacted by extreme rainfall, and with climate change this becomes even more important.
We were working on this project when the tragedy of the Carmont/Stonehaven derailment took place. Risk management on the railway makes use of many control measures, reducing risk to be as low as reasonably practicable. These measures are written into management processes that cover risks across the many diverse parts that make up the railway.
Thinking of the railway, we realise that railway operation is carried out in a complex, adaptive system. The follow up to the Carmont incident included independent reports on two parts of this complex system. Firstly, on geotechnical asset management led by past President of the ICE, Lord Robert Mair. Secondly on weather forecasting led by Dame Julia Slingo, formerly Chief Scientist at the Met Office. An interim report on the causes of the Carmont event was published by the Rail Accident Investigation Branch (RAIB) in May 2021.
Key messages from the Mair and Slingo reports show that weather hazard risk mitigation is complex when applied to earthworks and drainage assets. Consider how the British rail network was built by roughly 1850, there were no geotechnical standards or technical specifications until around 20-30 years later.
Consider how the slopes in these early earthworks tend to be steep, and that they were built in a rapid and risky way, unlike modern design and construction techniques with layers and compaction between layers. Risk mitigation is made more challenging because of climate change which is bringing more intense rainfall and increased storminess.
Remember that many other priorities exist in managing railway infrastructure, all requiring and competing for funding. These include general ‘wear and tear’ maintenance of all assets including tracks, signalling, overhead line and third rail power systems, bridges, and tunnels.
However, earthworks and drainage are significant systems in themselves and, as the Mair report mentioned, ought to be thought of systemically, as indeed track could be, knowing the influence of drainage and earthworks on track geometry. Indeed, as extreme weather and rainfall does not distinguish between different asset types, it is beneficial to think of all potentially affected assets as part of a system requiring a systemic response to their management.
The RAIB interim report highlights that the railway’s responses to severe weather events and weather-related infrastructure failures are still being considered. Its scope covers management systems and decision-making processes at times of wide-spread disruption caused by severe weather and/or multiple instances of infrastructure failure, and the use of weather data to help it manage events.
Forecasting the weather hazard, in this case extreme-rainfall induced surface-water, is not a solution in itself. Such a forecasting system needs to be integrated across the railway system. But how can such a system be integrated into the routine and emergency management of extreme weather using, in this case, the railway’s Extreme Weather Action process? Or into its maintenance preparations that include inspections of assets? Or even rapid responses? The answer; it can become an integral part of the risk management system – that involves many players.
Coming back to the proof of concept. Our trials have been successful, and we aim to show how its utility can bring a step-change in the management of surface water risk at our upcoming demonstration event.
Want to know more?
On 15 June we are hosting a virtual event for invited guests from the transport, utilities and insurance sectors, local authorities and academia, to demonstrate Flood Foresight’s surface water flood forecasting and early warning system, showcasing its ability to provide asset owners/managers with unique insight into flood events through a case study supported by Network Rail.
For more information about how Flood Foresight is aiding effective flood management around the world visit our dedicated webpage.